The present invention relates to a technique for manufacturing electronic or semiconductor devices. More particularly, the present invention provides a novel photolithography technique using, for example, an ArF light source (i.e., 193 nm), and a novel amine-introduced photoresist resin, which is suitable for photolithography using the ArF light source, but is not limited to this light source. In exemplary embodiments, the present invention provides techniques for using the novel photoresist resin in a lithography process for the manufacture of semiconductor integrated circuits or the like.
In the manufacture of highly integrated semiconductor devices, precisely controlled formation of structures is often required to form tiny regions, which form elements of electronic devices on a slice of silicon material. These regions are often created by way of a photolithography process. Photolithography often uses steps of spin coating a thin layer of photoresist material onto a surface of the slice of silicon or film on the silicon to be patterned. The thin layer of photoresist material is often selectively exposed using radiation such as ultraviolet light, electrons, or x-rays. An exposure tool such as a mask using a "stepper" selectively exposes the thin layer of photoresist material. The exposed regions of the thin layer are often developed by way of a chemical process. After development, the thin layer overlying the slice of silicon includes exposed regions which remain for subsequent processing. The subsequent processing step such as etching imprints the pattern made by the exposed region into the slice of silicon or film on the silicon.
Conventional optical photoresists are often three-component materials. These materials include a matrix material, commonly called the resin, which serves as a binder, and establishes the mechanical properties of the film. Additionally, the photoresist includes a sensitizer, commonly termed the inhibitor, which is a photoactive compound ("PAC"), and a solvent, which suspends the resist in a liquid state until it is applied to the substrate being processed. The resin is often inert to the incident imaging radiation and often does not undergo chemical change upon radiation, but provides the resist film with properties such as adhesion and etch resistance. Additionally, the resin provides other film properties such as resist thickness, flexibility, and thermal flow stability.
One example of a resin material is a conventional poly(acrylate) resin. The polyacrylate resin is often relatively easy to synthesize. For example, conventional polymerization techniques are often used to form this type of resin in many applications. Unfortunately, these resins have poor etch resistance and development characteristics. In some cases, etch resistance can be improved by introducing aliphatic ring moieties to the poly(acrylate) main polymer chain. Even in these cases, however, there still remain numerous other limitations. For example, development of conventional polyacrylate resin often produces a "roundish" upper resist edge, as shown in FIG. 1, for instance. Accordingly, the polyacrylate resin often cannot provide high resolution photoresist patterns but lower resolution patterns. These lower resolutions patterns simply cannot create accurate features for the manufacture of the highly integrated semiconductor devices.
From the above, it is seen that an improved photoresist product for producing high resolution patterns is highly desirable.